Added methods for gaining information about the view. This is useful for

applets such as systemtray and tasks that need to know about global
geometry.

svn path=/trunk/KDE/kdebase/workspace/libs/plasma/; revision=746172

widgets/widget.cpp

@@ -25,6 +25,8 @@
 #include <limits>
 
 #include <QApplication>
+#include <QGraphicsScene>
+#include <QGraphicsView>
 #include <QList>
 #include <QPainter>
 #include <QPixmapCache>
@@ -76,6 +78,36 @@ QGraphicsItem* Widget::graphicsItem()
     return this;
 }
 
+QGraphicsView *Widget::view() const
+{
+    // It's assumed that we won't be visible on more than one view here.
+    // Anything that actually needs view() should only really care about
+    // one of them anyway though.
+    if (!scene()) {
+        return 0;
+    }
+    foreach (QGraphicsView *view, scene()->views()) {
+        if (view->sceneRect().intersects(sceneBoundingRect())) {
+            return view;
+        }
+    }
+    return 0;
+}
+
+QRectF Widget::mapFromView(const QGraphicsView *view, const QRect &rect) const
+{
+    // TODO: Confirm that adjusted() is needed and is not covering for some
+    // issue elsewhere
+    return mapFromScene(view->mapToScene(rect)).boundingRect().adjusted(0, 0, 1, 1);
+}
+
+QRect Widget::mapToView(const QGraphicsView *view, const QRectF &rect) const
+{
+    // TODO: Confirm that adjusted() is needed and is not covering for some
+    // issue elsewhere
+    return view->mapFromScene(mapToScene(rect)).boundingRect().adjusted(0, 0, -1, -1);
+}
+
 bool Widget::Private::shouldPaint(QPainter *painter, const QTransform &transform)
 {
     Q_UNUSED(painter)

widgets/widget.h

@@ -30,6 +30,8 @@
 #include <plasma/layouts/layoutitem.h>
 #include <plasma/plasma_export.h>
 
+class QGraphicsView;
+
 namespace Plasma
 {
 
@@ -242,6 +244,25 @@ TODO: implement once we decide how to handle the font system
 
     virtual QGraphicsItem* graphicsItem();
 
+    /**
+     * Returns the view this widget is visible on
+     */
+    QGraphicsView *view() const;
+
+    /**
+     * Maps a QRect from a view's coordinates to local coordinates.
+     * @param view the view from which rect should be mapped
+     * @param rect the rect to be mapped
+     */
+    QRectF mapFromView(const QGraphicsView *view, const QRect &rect) const;
+
+    /**
+     * Maps a QRectF from local coordinates to a view's coordinates.
+     * @param view the view to which rect should be mapped
+     * @param rect the rect to be mapped
+     */
+    QRect mapToView(const QGraphicsView *view, const QRectF &rect) const;
+
 protected:
     /**
      * Paints the widget